EP0927890A3 - Shielded gradient coil assembly for magnetic resonance imaging system - Google Patents

Shielded gradient coil assembly for magnetic resonance imaging system Download PDF

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Publication number
EP0927890A3
EP0927890A3 EP98310706A EP98310706A EP0927890A3 EP 0927890 A3 EP0927890 A3 EP 0927890A3 EP 98310706 A EP98310706 A EP 98310706A EP 98310706 A EP98310706 A EP 98310706A EP 0927890 A3 EP0927890 A3 EP 0927890A3
Authority
EP
European Patent Office
Prior art keywords
current distribution
continuous current
magnetic field
magnetic
coil
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
EP98310706A
Other languages
German (de)
French (fr)
Other versions
EP0927890A2 (en
Inventor
Labros Petropoulos
Junxiao Ling
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Koninklijke Philips NV
Original Assignee
Marconi Medical Systems Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Marconi Medical Systems Inc filed Critical Marconi Medical Systems Inc
Publication of EP0927890A2 publication Critical patent/EP0927890A2/en
Publication of EP0927890A3 publication Critical patent/EP0927890A3/en
Ceased legal-status Critical Current

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Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R33/00—Arrangements or instruments for measuring magnetic variables
    • G01R33/20—Arrangements or instruments for measuring magnetic variables involving magnetic resonance
    • G01R33/28—Details of apparatus provided for in groups G01R33/44 - G01R33/64
    • G01R33/42—Screening
    • G01R33/421—Screening of main or gradient magnetic field
    • G01R33/4215—Screening of main or gradient magnetic field of the gradient magnetic field, e.g. using passive or active shielding of the gradient magnetic field
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R33/00—Arrangements or instruments for measuring magnetic variables
    • G01R33/20—Arrangements or instruments for measuring magnetic variables involving magnetic resonance
    • G01R33/28—Details of apparatus provided for in groups G01R33/44 - G01R33/64
    • G01R33/38—Systems for generation, homogenisation or stabilisation of the main or gradient magnetic field
    • G01R33/385—Systems for generation, homogenisation or stabilisation of the main or gradient magnetic field using gradient magnetic field coils

Landscapes

  • Physics & Mathematics (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • General Physics & Mathematics (AREA)
  • Health & Medical Sciences (AREA)
  • Epidemiology (AREA)
  • Magnetic Resonance Imaging Apparatus (AREA)

Abstract

A method of designing a shielded gradient coil assemblies for magnetic resonance imaging systems is provided. The method includes generating a first continuous current distribution for a primary coil (60) using an inverse approach. The first continuous current distribution is confined within predetermined finite geometric boundaries of a surface defined by two dimensions and generates a magnetic gradient field across an imaging region (14). The magnetic gradient field constrained to predetermined values at specified spatial locations within the imaging region (14). The current distribution and magnetic field are converted into a stored energy and magnetic field domain where a finite element analysis is performed to generate a second continuous current distribution for a shielding coil (62). The second continuous current distribution is confined within predetermined finite geometric boundaries of a surface surrounding the primary coil (60). The second continuous current distribution generates a magnetic field which substantially cancels in an area outside a region defined by the shielding coil a fringe magnetic field generated by the first continuous current density.
Figure 00000001
EP98310706A 1998-01-05 1998-12-23 Shielded gradient coil assembly for magnetic resonance imaging system Ceased EP0927890A3 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US3720 1998-01-05
US09/003,720 US6100692A (en) 1998-01-05 1998-01-05 Gradient coil set with a finite shield current

Publications (2)

Publication Number Publication Date
EP0927890A2 EP0927890A2 (en) 1999-07-07
EP0927890A3 true EP0927890A3 (en) 2001-05-02

Family

ID=21707257

Family Applications (1)

Application Number Title Priority Date Filing Date
EP98310706A Ceased EP0927890A3 (en) 1998-01-05 1998-12-23 Shielded gradient coil assembly for magnetic resonance imaging system

Country Status (3)

Country Link
US (1) US6100692A (en)
EP (1) EP0927890A3 (en)
JP (1) JPH11276457A (en)

Families Citing this family (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6201987B1 (en) * 1998-05-26 2001-03-13 General Electric Company Error compensation for device tracking systems employing electromagnetic fields
US6236203B1 (en) * 1998-09-28 2001-05-22 Picker International, Inc. Super shielding of finite length structures in open magnetic and electric systems
DE19947539B4 (en) * 1999-10-02 2006-04-20 Bruker Biospin Gmbh Gradient coil arrangement with damping of internal mechanical vibrations
US6278275B1 (en) * 1999-10-18 2001-08-21 Picker International, Inc. Gradient coil set with non-zero first gradient field vector derivative
JP3967505B2 (en) * 1999-12-07 2007-08-29 日本電子株式会社 Magnetic field correction coil design method
DE10010421C2 (en) * 2000-03-03 2002-01-17 Siemens Ag Method for operating a magnetic resonance tomography device and magnetic resonance tomography device
US6850066B2 (en) * 2003-05-15 2005-02-01 Ge Medical Systems Global Technology Company Llc Systems and methods for gradient compensation in magnetic resonance imaging
JP2006149722A (en) 2004-11-30 2006-06-15 Ge Medical Systems Global Technology Co Llc Magnet system and magnetic resonance imaging apparatus
DE102011077743B3 (en) * 2011-06-17 2012-11-22 Siemens Ag Method for producing a gradient coil assembly and winding mandrel
US9581665B2 (en) * 2012-04-20 2017-02-28 General Electric Company Systems and methods for damping common-mode energy
CN112612062B (en) * 2020-12-31 2023-12-19 上海太易检测技术有限公司 Gold inspection machine and gold inspection machine transmitting module
CN114545312B (en) * 2022-04-22 2022-09-09 浙江浙大西投脑机智能科技有限公司 Nonlinear gradient coil and scanning method

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4139420A1 (en) * 1990-11-30 1992-06-04 Toshiba Kawasaki Kk MRI device with actively screened gradient coil - has screen coils approximating eddy current distribution on imaginary cylindrical conductor
US5266913A (en) * 1991-08-27 1993-11-30 British Technology Group Usa Inc. Screened electromagnetic coil of restricted length having optimized field and method
US5296810A (en) * 1992-03-27 1994-03-22 Picker International, Inc. MRI self-shielded gradient coils

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4794338A (en) * 1987-11-25 1988-12-27 General Electric Company Balanced self-shielded gradient coils
JPH03182232A (en) * 1989-12-11 1991-08-08 Toshiba Corp Magnetic resonance imaging device
US5481191A (en) * 1990-06-29 1996-01-02 Advanced Nmr Systems, Inc. Shielded gradient coil for nuclear magnetic resonance imaging
US5488299A (en) * 1992-03-13 1996-01-30 Kabushiki Kaisha Toshiba Nuclear magnetic resonance imaging with improved image quality and operation efficiency

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4139420A1 (en) * 1990-11-30 1992-06-04 Toshiba Kawasaki Kk MRI device with actively screened gradient coil - has screen coils approximating eddy current distribution on imaginary cylindrical conductor
US5266913A (en) * 1991-08-27 1993-11-30 British Technology Group Usa Inc. Screened electromagnetic coil of restricted length having optimized field and method
US5296810A (en) * 1992-03-27 1994-03-22 Picker International, Inc. MRI self-shielded gradient coils

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
GOLDIE F T D: "SELF-SHIELDED GRADIENT COIL DESIGN VIA EDDY CURRENT MODELLING", MEETING AND EXHIBITION OF THE SOCIETY OF MAGNETIC RESONANCE IN MEDICINE,US,BERKELEY, SMRM, VOL. MEETING 7, PAGE(S) 120, XP000079449 *
TAKAO TAKAHASHI: "NUMERICAL ANALYSIS OF EDDY CURRENT PROBLEMS INVOLVING SADDLE-SHAPED COILS IN SUPERCONDUCTING MRI MAGNETS", IEEE TRANSACTIONS ON MAGNETICS,US,IEEE INC. NEW YORK, vol. 27, no. 5, 1 September 1991 (1991-09-01), pages 3996 - 3999, XP000237055, ISSN: 0018-9464 *
TURNER R: "GRADIENT COIL DESIGN: A REVIEW OF METHODS", MAGNETIC RESONANCE IMAGING,US,TARRYTOWN, NY, vol. 11, no. 7, 1993, pages 903 - 920, XP000537049, ISSN: 0730-725X *

Also Published As

Publication number Publication date
US6100692A (en) 2000-08-08
JPH11276457A (en) 1999-10-12
EP0927890A2 (en) 1999-07-07

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